Prior art pink (1/f) noise generation circuits are primarily used in audio engineering applications, and are inferior for several reasons. Some prior art noise generation circuits use noisy components, such as diodes, that lack the desired precision and tune-ability of the presently disclosed invention. Also, noise traces cannot be regenerated with these prior art noise generation circuits as the noise is not created using a deterministic pseudo-random process.
In the prior art, pink spectral shaping has been accomplished with standard 10 dB/decade low-pass filters which require impractically large components for ultra-low frequency operation in the sub audio frequency range.
Prior art noise signals are also intrinsically analog and thus cannot be used in an all-digital system.
A prior art pink noise generation algorithm in the context of audio engineering software development has been described by James McCartney and Larry Trammell in the web page http://www.firstpr.com.au/dsp/pink-noise/, which is incorporated herein by reference; however, the method is computationally complex and no circuit implementation is described.
What is needed is an all-digital noise generation circuit that produces pink (1/f) noise. Further, it is desirable that the generated pink noise has a tunable amplitude, has no low frequency cutoff, and be able to be regenerated. The embodiments of the present disclosure answer these and other needs.